In professional Mumbai or Delhi society, no one seems to care much. You are a banker, a lawyer or a programmer. For the most part, you get your job or start your business via your own professional connections. Personal and professional life is separated very much like it is in the west.
Outside of this fairly narrow circle, family/family friends/clannish identity is more or less merged with your professional identity. Want to start a business? There is a good chance you share a last name with your investors and business partners. Want a bank loan? Better be connected to the loan officer. It's also helpful if you are connected to the various government workers who's permission you will need to start your business [1], and you'll get better service if your supplier is your second cousin.
The value of your network is a superlinear function of it's size. If Muslims have a smaller network, they are probably disadvantaged.
[1] I recently met a guy who wanted to start a business selling eye tracking devices. He scrapped the idea because he needed 34 licenses.
